Saccharomyces polysaccharide from, structure

Yeast Insoluble Polysaccharide. The structure of an insoluble polysaccharide from the yeast Saccharomyces cerevisiae was investigated by Zechmeister and Toth,90a and also by Hassid, Joslyn and McCready.904 The isolation904 of 2,4,6-trimethyl-D-glucose as the sole product of the hydrolysis of the methylated polysaccharide indicated a chain of gluco-pyranose units joined by 1,3-glucosidic linkages. 

The structure of mannose-rich polysaccharide core in GL4 is close to that of yeast mannan (from Saccharomyces cerevisiae), which was inactive for IL-6 induction in a human peripheral whole-blood cells test system. This fact suggests that not the mannose moieties but other components, such as the lipophilic moiety and/or phosphates, are important for the activity. The lipophilic products in HF-hydrolysate of GL4 were then analyzed. In addition to peaks corresponding to the known fatty acids (C16 0, C18 1), two other unknown ion peaks at m/z 330 and 356 were found by FAB-MS (data not shown). 

The constituents together form a complex network, and any of the separable polysaccharide fractions may be absent, or vary qualitatively and quantitatively from one kind of yeast to another. In particular, there are qualitative differences between the mannans of various species. Major structural differences are also found, because, unlike ascosporogenous yeasts, such as Saccharomyces species, basi-diomycetous yeasts100 appear to have multilayered walls.101,102... 

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